Investigation of Anti-inflammatory, Antipyretic and Analgesic Activities of Citrullus colocynthis in Albino Rats through in vivo and Pharmacoinformatics Studies.

INTRODUCTION: Hyperpyrexia, algesia and inflammation are pathological disorders which are treated with synthetic as well as herbal medications. AIMS: The basic aim of the present study is to evaluate the ethnopharmacological activities of phytoconstituents that are present in C. colocynthis (fruit extract) by using in vivo and in silico studies. METHODS: Thirty-six albino rats were used in our studies with an average weight between 150-170 g. Anti-inflammatory activity was investigated using carrageenan (an extract from a red seaweed) that induced edema in albino rat paws. However, in antipyretic and analgesic activity studies, yeast and acetic acid were used to cause pyrexia or algesia, respectively. Different doses of acetone fruit extract were used to treat inflammation, pyrexia and algesia. RESULTS: Our results showed that the maximum percentage inhibition of acetonic fruit extract in anti-inflammatory and analgesic activities was observed at 70% and 100%, respectively, with 400 mg/kg doses, and in pyretic activity the maximum inhibitory percentage was 86% with a 100 mg/kg dose. In in silico analysis, we have shown that bioactive compounds (α-spinasterol, ascorbic acid and chlorogenic acid) found in fruit extract have outstanding inhibition properties that involves proteins PTGS2, TLR2 and TRPV4. C. colocynthis fruit extract shows results that are statistically significant (p < 0.005) and comparable to a reference drug. Acetonic fruit extract of C. colocynthis can be used as a natural and safe remedy with no side effects. CONCLUSION: Both in vivo and in silico studies on chlorogenic acid, ascorbic acid and α-spinasterol have shown that these are inhibitory compounds that can be used for boosting the immune response.

Network pharmacology integrated with experimental verification reveals the antipyretic characteristics and mechanism of Zi Xue powder.

CONTEXT: Zi Xue Powder (ZXP) is a traditional formula for the treatment of fever. However, the potential mechanism of action of ZXP remains unknown. OBJECTIVE: This study elucidates the antipyretic characteristics of ZXP and the mechanism by which ZXP alleviates fever. MATERIALS AND METHODS: The key targets and underlying fever-reducing mechanisms of ZXP were predicted using network pharmacology and molecular docking. The targets of ZXP anti-fever active ingredient were obtained by searching TCMSP, STITCH and HERB. Moreover, male Sprague-Dawley rats were randomly divided into four groups: control, lipopolysaccharide (LPS), ZXP (0.54, 1.08, 2.16 g/kg), and positive control (acetaminophen, 0.045 g/kg); the fever model was established by intraperitoneal LPS injection. After the fever model was established at 0.5 h, the rats were administered treatment by gavage, and the anal temperature changes of each group were observed over 10 h after treatment. After 10 h, ELISA and Western blot analysis were used to further investigate the mechanism of ZXP. RESULTS: Network pharmacology analysis showed that MAPK was a crucial pathway through which ZXP suppresses fever. The results showed that ZXP (2.16 g/kg) decreased PGE2, CRH, TNF-a, IL-6, and IL-1ß levels while increasing AVP level compared to the LPS group. Furthermore, the intervention of ZXP inhibited the activation of MAPK pathway in LPS-induced fever rats. CONCLUSIONS: This study provides new insights into the mechanism by which ZXP reduces fever and provides important information and new research ideas for the discovery of antipyretic compounds from traditional Chinese medicine.

Protective mechanisms of Tuina therapy against lipopolysaccharide-induced fever in young rabbits based on untargeted metabolomics analysis.

OBJECTIVE: To investigate the effect of Tuina on the plasma metabolites of lipopolysaccharide-induced febrile in infant rabbits. METHODS: Twenty-four infant New Zealand rabbits were selected and randomly divided into three groups: saline, model, and Tuina. The fever model was established by injecting LPS intravenously through the ear margin vein in the model group and Tuina group, respectively. The modeling was considered successful when the anal temperature increased by 0.5℃ or above within 1 h. In the Tuina group, six Tuina techniques (i.e., opening Tianmen / the heaven gate, pushing Kangong / the superciliary arch, kneading Taiyang and the prominent bone behind the ears, clearing Tianheshui, spine pinching) that alleviate fever were performed on the young rabbits 1 h after the modeling, whereas the model and saline groups were not given Tuina treatment, with the real-time anal temperature monitored during the experiment. The plasma was taken 3 h after the modeling for liquid chromatography-mass spectrometry (LC-MS) untargeted metabolomics study. RESULTS: Our results showed a fever-reducing effects of Tuina therapy on lipopolysaccharide-induced fever in young rabbits, as indicated by a significantly lower anal temperature, maximum rise in body temperature, and body response index at 2 and 3 h after modeling in the Tuina group compared to the model group, with reductions in the PGE2 expression observed in the blood and hypothalamus. The differential metabolites including riboflavin, nicotinamide N-oxide, porphobilinogen, 5-hydroxyindoleacetic acid, gamma-aminobutyric acid, and lysoPC (16:1 (9Z)/0:0) were found following the Tuina intervention. Tuina primarily involves glycine-serine-threonine, arginine-proline, porphyrin-chlorophyll, pyrimidine, primary bile acid biosynthesis, and cyanoamino acid metabolic pathways. CONCLUSION: Tuina therapy has proven to be effective in reducing body temperature and down-regulating PGE2 expression in LPS-induced febrile young rabbits, with its mechanism of fever-reducing action possibly associated with the changes in plasma metabolites and metabolic pathways.

Bupleurum chinense exerts a mild antipyretic effect on LPS-induced pyrexia rats involving inhibition of peripheral TNF-α production.

ETHNOPHARMACOLOGICAL RELEVANCE: Bupleuri Radix, the dried roots of Bupleurum chinense DC. (BC) or Bupleurum scorzonerifolium Willd., is one of the most frequently used traditional Chinese medicines. As the species in Xiao-Chai-Hu decoction, BC has been used as an antipyretic medicine with a long history. However, its antipyretic characteristics and underlying mechanism(s) remain unclear. AIM OF THE STUDY: To elucidate the antipyretic characteristics and mechanism(s) of BC used in its traditional way. METHODS: The water extract of BC (BCE) was prepared according to the traditional decocting mode. Murine fever and endotoxemia models were induced by intravenous injection of lipopolysaccharide (LPS). In vitro complement activation assay and the levels of TNF-α, IL-6, IL-1ß, and C5a were determined by ELISA. RESULTS: BCE exerted a confirmed but mild antipyretic effect on LPS-induced fever of rat. In vitro, it significantly lowered LPS-elevated TNF-α in the supernatant of rat complete blood cells and THP-1 cells, but failed to decrease IL-6 and IL-1ß. In murine endotoxemia models, BCE markedly decreased serum TNF-α, but had no impact on IL-6 and IL-1ß. BCE also restricted complement activation in vitro and in vivo. Nevertheless, the mixture of saikosaponin A and D could not suppress supernatant TNF-α of monocytes and serum TNF-α of endotoxemia mice. CONCLUSIONS: The present study dissects the peripheral mechanism for the antipyretic effect of BC used in the traditional way. Our findings indicate that BCE directly suppresses monocyte-produced TNF-α, thus decreasing circulating TNF-α, which may be responsible for its mild but confirmed antipyretic action.

Comparing the effect of body wash with marshmallow plant and lukewarm water on reducing the temperature of febrile children: a randomized clinical trial.

BACKGROUND: Fever is the most common reason for children's visits to medical centers. Its management is an essential duty of a pediatric nurse. The aim of this study was to determine the effect of body wash with Marshmallow plant on children's fever. METHODS: This parallel clinical trial was performed on 92 children aged 6 months to 10 years with a tympanic temperature above 38.3 °C. Participants were randomly assigned to groups. Simultaneously with receiving acetaminophen, body wash was performed in the control group with lukewarm water and in the intervention group with white Marshmallow extract. The children's temperature; from the beginning of the study was checked and recorded every 15 min in the first hour and in the 4th and 6th hours. The time duration to resolve fever, the frequency of afebrile children at different times of the study, and the value of temperature reduction were primary outcomes. Heart rate, the need to administer the next dose of acetaminophen, and the time of fever recurrence were recorded as secondary outcomes. RESULTS: The mean time duration to resolve fever in the intervention group was shorter than in the control group (B = 8.181, 95% CI 3.778-12.584, p < 0.001). The frequency of the children without fever was higher in the intervention group during different times of the study (p < 0.001). The mean value of temperature reduction in the intervention group was higher than the control group (B = -0.27 °C, 95% CI: -0.347 to -0.193, P < 0.001), although, after adjusting the effect of confounding variables it was not significant (P = 0.127). The mean of adjusted heart rate change (p = 0.771), the time of fever recurrence (P = 0.397), and the frequency of children requiring the next dose of acetaminophen (p = 0.397) did not show a significant difference between the groups. CONCLUSION: Body wash with Marshmallow extract reduced children's fever in a shorter period of time and to some extent a greater extent than the control group without side effects. Therefore, it can be used as an effective and safe complementary method to help reduce fever. However, more studies are necessary for this field. TRIAL REGISTRATION: Registration in Iranian Clinical Trials (RCTs) on 31.08.2020 with registration code: IRCT20200809048345N1.

Anti-Inflammatory, analgesic and anti-pyretic activity of Fagonia bruguieri DC in rats.

Traditional medicine has employed the plant Fagonia bruguieri DC. to alleviate inflammation, fever and pain. The goal of this study was to test the anti-inflammatory, analgesic and antipyretic properties of the methanol extract of whole plant of Fagonia bruguieri (F. bruguieri). The writhing test and Eddy's hot plate test were used to assess the analgesic potential of F. bruguieri at three different doses. Carrageenan-induced rat paw edema was applied to investigate anti-inflammatory activity, whereas antipyretic activity was estimated in Brewer's yeast induced pyrexia model. Flavonoids, alkaloids, saponins, tannins and glycosides were found in F. bruguieri's phytochemical analysis. F. bruguieri at 750 mg/kg reduced writhing count by 62.23 percent, while F. bruguieri enhanced latency in Eddy's hot plate test. In carrageenan-induced edema, F. bruguieri at 750 mg/kg exhibited considerable anti-inflammatory effect (41.11 percent) after 2 nd, 3 rd and 4 th hours of therapy. F. bruguieri was also found to show antipyretic properties. The anti-inflammatory, analgesic and antipyretic properties of F. bruguieri were confirmed in this study, which might be attributable to the presence of several phyto-constituents.

Neural circuits mediating circulating interleukin-1ß-evoked fever in the absence of prostaglandin E2 production.

Infectious diseases and inflammatory conditions recruit the immune system to mount an appropriate acute response that includes the production of cytokines. Cytokines evoke neurally-mediated responses to fight pathogens, such as the recruitment of thermoeffectors, thereby increasing body temperature and leading to fever. Studies suggest that the cytokine interleukin-1ß (IL-1ß) depends upon cyclooxygenase (COX)-mediated prostaglandin E2 production for the induction of neural mechanisms to elicit fever. However, COX inhibitors do not eliminate IL-1ß-induced fever, thus suggesting that COX-dependent and COX-independent mechanisms are recruited for increasing body temperature after peripheral administration of IL-1ß. In the present study, we aimed to build a foundation for the neural circuit(s) controlling COX-independent, inflammatory fever by determining the involvement of brain areas that are critical for controlling the sympathetic outflow to brown adipose tissue (BAT) and the cutaneous vasculature. In anesthetized rats, pretreatment with indomethacin, a non-selective COX inhibitor, did not prevent BAT thermogenesis or cutaneous vasoconstriction (CVC) induced by intravenous IL-1ß (2 µg/kg). BAT and cutaneous vasculature sympathetic premotor neurons in the rostral raphe pallidus area (rRPa) are required for IL-1ß-evoked BAT thermogenesis and CVC, with or without pretreatment with indomethacin. Additionally, activation of glutamate receptors in the dorsomedial hypothalamus (DMH) is required for COX-independent, IL-1ß-induced BAT thermogenesis. Therefore, our data suggests that COX-independent mechanisms elicit activation of neurons within the DMH and rRPa, which is sufficient to trigger and mount inflammatory fever. These data provide a foundation for elucidating the brain circuits responsible for COX-independent, IL-1ß-elicited fevers.

Complete Pathologic Response to Neoadjuvant Chemoimmunotherapy and Oxaliplatin-Induced Fever Associated With IL-6 Release in a Patient With Locally Advanced Colon Cancer

Neoadjuvant systemic therapy is a preferred treatment approach for a number of tumor types due to many potential advantages over upfront surgery, including tumor downstaging, early treatment of micrometastatic disease, and providing an in vivo test of tumor biology. For colon cancer, current standard of care is upfront surgery followed by adjuvant systemic therapy in high-risk patients. Concerns about inaccurate radiological staging and tumor progression during preoperative treatment, as well the lack of randomized data demonstrating benefit, are among the reasons for the limited use of neoadjuvant therapy in this disease. Locally advanced colon cancer, defined as primary colon cancer with direct invasion into the adjacent structures or extensive regional lymph node involvement, is not always amenable to pathological complete resection, and when attempted it comes with high incidence of postoperative morbidity and mortality because of the required multivisceral resection. Clinical trials of neoadjuvant chemotherapy for colon cancer to date have been promising with downstaging of disease and higher rates of R0 resection. Here, we report a case of a patient with locally advanced, unresectable, mismatch repair deficient sigmoid colon cancer who was treated with neoadjuvant chemoimmunotherapy followed by surgical resection leading to a complete pathologic response after preoperative systemic chemoimmunotherapy.

Investigations of the antipyretic effect and safety of Prasachandaeng, a traditional remedy from Thailand national list of essential medicines.

Prasachandaeng (PSD) remedy from the Thailand National List of Essential Medicines (NLEM) has been used as an antipyretic for chronic fever in both adults and children for centuries. Its therapeutic effect in treating fever and its safety have not been studied in animal models. We evaluated its antipyretic activity on lipopolysaccharide (LPS)-induced fever and safety in the liver in comparison with acetaminophen (ACP). Correlation between biochemistry of liver function and the level of cytochrome P450 (CYP2E1) was also evaluated using an ELISA kit. All doses of PSD powder (PSDP) and a 95% ethanol extract of PSD (PSDE) (50, 200, and 400 mg/kg) showed a significant antipyretic effect (* p < 0.05) as compared to ACP. We investigated clinical biochemistry of liver and kidney functions, histopathology, and concentrations of CYP2E1. All treatment groups demonstrated a normal range of clinical biochemistry of liver and kidney functions in comparison with ACP on days 1, 3, 7, and 10. Serum AST, ALP, and LDH levels of PSDE and PSDP showed mean values less than that of ACP on the corresponding days (* p < 0.05). None of the treatment groups showed evidence of hepatocellular damage, nor did they affect CYPE21. The results of histopathology on liver tissue correlated with the biochemistry of liver functions which indicated no hepatotoxicity effect in liver tissue during the seven day treatment. These findings suggest that both forms of PSD remedy possessed marked antipyretic activity and were not hepatotoxic during the seven days of administration in rats.

Bai-Hu-Tang regulates endothelin-1 and its signalling pathway in vascular endothelial cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Bai-Hu-Tang (BHT) is traditionally used to treat human and animal fever syndrome with four symptoms: large and vigorous pulse, large thirst, high sweat, and high heat. AIM OF THE STUDY: To investigate the mechanism of vasodilation regulation of Bai-Hu-Tang in primary vascular endothelial cells stimulated by lipopolysaccharide (LPS). MATERIALS AND METHODS: A hydrophilic concentrate of BHT was prepared, and the main components of mangiferin and timosaponin BⅡ were determined by HLPC analysis. The rabbit fever model was constructed by intravenous injection of LPS (15 µg/kg body weight), and BHT was gavaged to treat febrile rabbits. After treatment for 6 h, animal peripheral blood was collected, and serum was isolated for endothelin-1 (ET-1) and nitric oxide (NO) assays. Rabbit vascular endothelial cells (RVECs) were isolated and stimulated with 1 µg/mL LPS, and then inflammatory cells were treated with 125 or 250 µg/mL BHT for 24 h. The supernatant cytokines TNF-ɑ, IL-1ß, IL-6, and ET-1 were detected by ELISA kits. Gene expression levels of endothelin receptor type B (ETB receptor) were analysed by real-time polymerase chain reaction (RT-PCR), and protein expression levels of PI3K and Akt were detected by Western blot. A nitrite assay was used to measure intracellular nitric oxide (NO) production, and nitric oxide synthase (NOS) was measured by the T-NOS colorimetric method. RESULTS: Animal experiments demonstrated that BHT significantly restored ET-1 and NO in animal peripheral blood, which were disordered in LPS-induced fever rabbits. Moreover, a cytotoxicity assay demonstrated that BHT ≤700 µg/mL is innoxious to RVECs. BHT significantly repressed cellular TNF-α, IL-1ß, and ET-1, which were originally elevated by LPS in RVECs. Meanwhile, BHT elevated the gene expression level of the ETB receptor and promoted NOS and NO production in RVECs induced by LPS. CONCLUSION: BHT can inhibit excessive ET-1 secretion induced by LPS in vascular endothelial cells and activate the classic ET-1 signalling pathway to promote NO production, which may facilitate vasodilation of smooth muscle cells.

The hyperthermic effect of central cholecystokinin is mediated by the cyclooxygenase-2 pathway.

Cholecystokinin (CCK) increases core body temperature via CCK2 receptors when administered intracerebroventricularly (icv). The mechanisms of CCK-induced hyperthermia are unknown, and it is also unknown whether CCK contributes to the fever response to systemic inflammation. We studied the interaction between central CCK signaling and the cyclooxygenase (COX) pathway. Body temperature was measured in adult male Wistar rats pretreated with intraperitoneal infusion of the nonselective COX enzyme inhibitor metamizol (120 mg/kg) or a selective COX-2 inhibitor, meloxicam, or etoricoxib (10 mg/kg for both) and, 30 min later, treated with intracerebroventricular CCK (1.7 µg/kg). In separate experiments, CCK-induced neuronal activation (with and without COX inhibition) was studied in thermoregulation- and feeding-related nuclei with c-Fos immunohistochemistry. CCK increased body temperature by ∼0.4°C from 10 min postinfusion, which was attenuated by metamizol. CCK reduced the number of c-Fos-positive cells in the median preoptic area (by ∼70%) but increased it in the dorsal hypothalamic area and in the rostral raphe pallidus (by ∼50% in both); all these changes were completely blocked with metamizol. In contrast, CCK-induced satiety and neuronal activation in the ventromedial hypothalamus were not influenced by metamizol. CCK-induced hyperthermia was also completely blocked with both selective COX-2 inhibitors studied. Finally, the CCK2 receptor antagonist YM022 (10 µg/kg icv) attenuated the late phases of fever induced by bacterial lipopolysaccharide (10 µg/kg; intravenously). We conclude that centrally administered CCK causes hyperthermia through changes in the activity of "classical" thermoeffector pathways and that the activation of COX-2 is required for the development of this response.NEW & NOTEWORTHY An association between central cholecystokinin signaling and the cyclooxygenase-prostaglandin E pathway has been proposed but remained poorly understood. We show that the hyperthermic response to the central administration of cholecystokinin alters the neuronal activity within efferent thermoeffector pathways and that these effects are fully blocked by the inhibition of cyclooxygenase. We also show that the activation of cyclooxygenase-2 is required for the hyperthermic effect of cholecystokinin and that cholecystokinin is a modulator of endotoxin-induced fever.

Pharmacological investigation of analgesic and antipyretic activities of methanol extract of the whole part of Aeginetia indica.

ETHNOPHARMACOLOGICAL RELEVANCE: Aeginetia indica (Linn.), commonly known as aankuri bankuri, guan-jen-huang, forest ghost flower, dok din daeng, dapong tubo; is a root parasitic plant of the Orobanchaceae family native to South and South-East Asian region. Different parts of the plant are traditionally used to treat fever, pain, inflammation, arthritis, cough, diabetes, and chronic liver disease. Local practitioners often recommend this plant as a folk remedy for dermal swelling, painful menstrual periods, wounds, and knee pain. However, the antipyretic and analgesic activity of A. indica have never been investigated. AIM OF THE STUDY: The present study was aimed to evaluate the analgesic and antipyretic potential of Aeginetia indica plant extract to verify its effectiveness as reported in traditional uses. MATERIALS AND METHODS: Preliminary phytochemical analysis of Aeginetia indica crude extract was performed using previously established methods and antioxidant capacity was determined by phosphomolybdenum assay. In vivo analgesic activity of Aeginetia indica methanol extract (AiME) was evaluated by acetic acid-induced writhing test, formalin-induced paw licking test, and hot plate test model. The antipyretic activity was studied in Baker's yeast induced pyrexia model. RESULTS: Phytochemicals screening revealed cardiac glycosides, saponins, phenols, tannins, and flavonoids in the crude extract of Aeginetia indica. Total phenolic and flavonoid content were recorded as 101 ± 1.1 mg GAE/g of the extract and 35 ± 0.8 mg QE/g of the extract, respectively. The total antioxidant capacity observed in phosphomolybdenum assay was 68.3 ± 1.3 mg ascorbic acid equivalent per gram of the extract. AiME showed significant dose-dependent analgesic activity against acetic acid-induced writhing, formalin-induced paw licking, and hot plate pain model. A higher dose of A. indica (200 mg/kg) produced significant (P < 0.001) inhibition of writhing by 69% whereas, standard aspirin showed maximum 85.6% inhibition. AiME at all doses showed a significant (P < 0.001) decrease of paw licking time in both early neurogenic and late inflammatory pain phase of formalin-induced licking test. In the hot plate test, AiME at a 200 mg/kg dose produced antinociceptive activity (55.18%) higher than the standard ketorolac (49.88%) at 1 h. However, after 2 h, ketorolac showed a maximum effect of 62.66% and AiME 200 mg/kg showed a 60.24% effect. A significant (P < 0.001) reduction of rectal temperature (4.54 °F↓) was recorded for AiME 200 mg/kg, which was higher than the standard paracetamol (3.86 F°↓) after 24 h of treatment. CONCLUSION: The in vivo investigational studies' results demonstrated promising analgesic and antipyretic activities of A. indica, which supported the claim of its folk uses.

Antiinflammatory properties of antiLy6G antibody disappear during magnetic field exposure in rats with carrageenan induced acute paw inflammation.

Antiinflammatory properties of pulsed magnetic field (PMF) treatments or administration of antiLy6G antibody have been previously reported. In this study, we hypothesized that, the combination of PMF treatments and antiLy6G administration may synergistically potentiate their antiinflammatory actions. The effects of the combination of PMF treatments and antiLy6G administration were investigated by examining the inflammatory signs, histopathological properties of the inflamed site, and measuring the macrophage inflammatory protein-1 alpha (MIP-1α/CCL3) and myeloperoxidase (MPO) levels of inflamed paw tissues in rats with carrageenan-induced acute paw inflammation. In this present study, PMF treatments alone or administration of antiLy6G alone ameliorated the acute inflammation. However, their combination exacerbated the inflammatory signs, hyperalgesia, allodynia, edema and fever, and aggravated the inflammatory conditions by excessive infiltration of inflammatory cells to the inflamed site. These opposing effects of the combined treatments may correlate with enhanced levels of MIP-1α and MPO in inflamed paws. Present results indicated that the combination of the PMF treatments and antiLy6G administration may not provide additional benefits and may actually cause an aggravation of the acute inflammatory process. Findings may also suggest that during neutrophil or immune cell-targeted treatments for inflammatory states, magnetic field exposure may cause unexpected negative consequences.

Presence of mother prompts dissociation of sickness behavior, fever, and hypothalamic gene expression in lipopolysaccharide-injected guinea pig pups.

During infection, sickness behaviors, such as a hunched stance with piloerection, can facilitate host resistance by supporting the generation and maintenance of fever. Fever, in turn, is mediated by hypothalamic neuroimmune signaling. Sickness behaviors, however, can also be influenced by social stimuli. In this study, guinea pig pups were injected with lipopolysaccharide to simulate a bacterial infection and then exposed to a novel, threatening environment while either with their mother or alone. We found that the presence of the mother suppressed sickness behavior, but enhanced fever, and had no measureable effect on gene expression of hypothalamic mediators of fever. This 3-way dissociation induced by the mother's presence is interpreted in terms of the differential adaptive consequences of behavioral and febrile responses for pups in this situation. The results contribute to a growing literature linking immunological and social processes.

Antipyretic, anti-inflammatory and analgesic activities of Periplaneta americana extract and underlying mechanisms.

Periplaneta americana is a common traditional Chinese medicinal material which has been used to treat arthritis, fever, aches, pains, and inflammation of the extremities for several hundred years. However, little scientific data exists in literature to support its use. The purpose of this study was to evaluate the antipyretic, anti-inflammatory and analgesic activities of Periplaneta americana extract (PAE) and explore its underlying mechanism. The antipyretic, anti-inflammatory and analgesic activities were evaluated by LPS-induced fever, carrageenan-induced paw edema, abdominal writhing, hot plate and formalin tests, respectively. The mechanism of action was explored by antioxidant activity analysis, inflammatory cytokines expression and febrile mediator measurement, and pathway activation analysis. The results from UHPLC-HRMS indicated that the extract was found to contain dopamine, coumarin, dipeptide, vitamin, organic acid, amino acid and its metabolites, and other organic compounds. PAE showed in a dose-dependent manner antioxidant activity and reduced the protein production and mRNA expression of NO, IL-1ß, IL-6, and TNF-α in RAW 264.7 cells in vitro. Moreover, PAE significantly and dose-dependently inhibited the writhing responses and licking time in formalin tests, increased response latency in the hot plate test, reduced carrageenan-induced paw edema and inflammation in mice, decreased LPS-induced rT increase in rats. Furthermore, PAE treatment markedly inhibited the increase in the levels of NO, IL-6, IL-1ß, TNF-α, PGE2 and cAMP in plasma of fevered rat, greatly suppressed the activation of inflammatory response pathway and the change of MDA and GSH concentration, MPO and SOD activity as well as FRAP capacity in paw induced by carrageenan injection. In conclusion, the findings suggested that PAE produced potential antinociceptive, anti-inflammatory and antipyretic effects by reducing production of endogenous inflammatory mediators and blocking the MAPK/NF-κB signaling pathway which support the claim for its traditional use in the treatment of various diseases.

Central leukotrienes modulate fever tolerance to LPS in rats.

Leukotrienes mediate several inflammatory events such as neutrophil chemoattraction, leukocyte adhesion, and central-release of cytokines and fever. However, there is no information available about their putative role in lipopolysaccharide (LPS) tolerance. The rational of the present study was to find out if central leukotrienes are involved in the development of LPS tolerance. Thus, we inhibited central leukotriene synthesis in tolerant rats using a pharmacological tool, i.e., a selective inhibitor of leukotriene synthesis MK-886 injected into the third ventricle (3V) of rats. Body core temperature (Tb) was measured using a datalogger placed inside the abdominal cavity. A low-dose of LPS (100 µg/kg ip) was given for 4 consecutive days to induce LPS tolerance. At day 4, rats received a microinjection of MK-886 into the 3V immediately before LPS, whereas control groups were treated with vehicle (saline). We observed that LPS failed to induce plasma cytokines surges, increased hypothalamic PGE2 levels and fever 3 days post LPS treatment, aptly characterizing the tolerance. When MK-886 was given to control rats treated with saline, no significant change in Tb was observed. However, a full LPS-induced fever was observed in tolerant rats pretreated with MK-886, which was associated with an enhancement in the hypothalamic PGE2 levels, that were not accompanied by plasma cytokines (IL-1ß, and IL-6) and PGE2 surges. These data are consistent with the notion that central leukotrienes play a role in fever tolerance to LPS.

In-vivo Assessment of Antipyretic and Anti-inflammatory Activities of Gymnosporia Royleana Extract in Mice / Evaluación in vivo de las Actividades Antipiréticas y Antiinflamatorias del Extracto de Gymnosporia Royleana en Ratones

ABSTRACT Objective: Despite the presence of multitude of synthetic drugs against fever and inflammation, none has been proven entirely safe. In contrast, the accepted safety of plant derived natural products is inspiring the world. Based on this fact as well as in view of the diversified activities reported from the genus Gymnosporia, the present study was designed to evaluate the antipyretic and anti-inflammatory activity of Gymnosporia royleana (G royleana). Methods: The methanolic extract of the aerial parts of G royleana was screened for in-vivo antipyretic activity using the brewer's yeast-induced pyrexia mice model and for anti-inflammatory activity using the carrageenan-induced paw oedema and xylene-induced ear oedema mice model. Results: In the antipyretic assay, G royleana extract showed considerable antipyretic activity in a dose dependent fashion. Statistically significant antipyretic effects (p < 0.05) were observed at the end of the second hour of administration for all doses of extract and remained significant until the end of the experiment. The plant extract also displayed promising anti-inflammatory activity, in a dose dependent fashion, in both models of inflammation ie carrageenan- and xylene-induced oedema models, when compared to the controls. In the carrageenan-induced oedema model, significant effects (p < 0.01) were observed for 300 and 600 mg/kg doses after 60 minutes of xylene administration (ie 55.51% and 65.88% inhibition of oedema, respectively). Conclusion: The study provided evidence supporting the antipyretic and anti-inflammatory activity of the G royleana methanolic extract.

RESUMEN Objetivo: A pesar de la presencia de multitud de fármacos sintéticos en el arsenal contra la fiebre y la inflamación, ninguno ha dado pruebas de ser completamente seguro. En contraste con ello, la seguridad aceptada de los productos naturales derivados de las plantas inspira al mundo. Sobre la base de este hecho, así como en vista de las actividades diversificadas que se reportan con respecto al género Gymnosporia, el presente estudio se diseñó con el objeto de evaluar el potencial antipirético y antiinflamatorio de Gymnosporia royleana (G royleana). Métodos: El extracto de metanol de las partes aéreas de G royleana fue tamizado en busca de actividad antipirética in vivo, utilizando el modelo de pirexia inducida por levadura de cerveza en ratones, y de actividad antiinflamatoria utilizando modelos de ratones con oedema de las patas inducido mediante carragenina, y oedema de las orejas inducido mediante xileno. Resultados: En el ensayo antipirético, el extracto de G royleana mostró una actividad antipirética considerable en forma dependiente de la dosis. Se observó un efecto antipirético estadísticamente significativo (p < 0.05) en el transcurso de la segunda hora de administración para todas las dosis de extracto y se mantuvo significativo hasta el final del experimento. El extracto de la planta también mostró una actividad antiinflamatoria prometedora, de una manera dependiente de la dosis, en ambos modelos de inflamación, es decir, modelos de oedema inducido por carragenina y xileno, en comparación con el control. En el modelo de oedema inducido por carragenina, se observó un efecto significativo (p < 0.01) para dosis de 300 y 600 mg / kg después de 60 minutos de administración de xileno (es decir, 55.51% y 65.88% de inhibición del oedema, respectivamente). Conclusión: El estudio proporcionó pruebas suficientes sobre el potencial antipirético y antiinflamatorio del extracto de G royleana.

The influence of the host microbiome on 3,4-methylenedioxymethamphetamine (MDMA)-induced hyperthermia and vice versa.

Hyperthermia induced by 3,4-methylenedioxymethamphetamine (MDMA) can be life-threatening. Here, we investigate the role of the gut microbiome and TGR5 bile acid receptors in MDMA-mediated hyperthermia. Fourteen days prior to treatment with MDMA, male Sprague-Dawley rats were provided water or water treated with antibiotics. Animals that had received antibiotics displayed a reduction in gut bacteria and an attenuated hyperthermic response to MDMA. MDMA treated animals showed increased uncoupling protein 1 (UCP1) and TGR5 expression levels in brown adipose tissue and skeletal muscle while increased expression of UCP3 was observed only in skeletal muscle. Antibiotics prior to MDMA administration significantly blunted these increases in gene expression. Furthermore, inhibition of the TGR5 receptor with triamterene or of deiodinase II downstream of the TGR5 receptor with iopanoic acid also resulted in the attenuation of MDMA-induced hyperthermia. MDMA-treatment enriched the relative proportion of a Proteus mirabilis strain in the ceca of animals not pre-treated with antibiotics. These findings suggest a contributing role for the gut microbiota in MDMA-mediated hyperthermia and that MDMA treatment can trigger a rapid remodeling of the composition of the gut microbiome.

Role of CINC-1 and CXCR2 receptors on LPS-induced fever in rats.

The classic model of fever induction is based on the administration of lipopolysaccharide (LPS) from Gram-negative bacteria in experimental animals. LPS-induced fever results in the synthesis/release of many mediators that assemble an LPS-fever cascade. We have previously demonstrated that cytokine-induced neutrophil chemoattractant (CINC)-1, a Glu-Leu-Arg (ELR) + chemokine, centrally administered to rats, induces fever and increases prostaglandin E2 in the cerebrospinal fluid. We now attempt to investigate the involvement of CINC-1 and its functional receptor CXCR2 on the fever induced by exogenous and endogenous pyrogens in rats. We also investigated the effect of reparixin, an allosteric inhibitor of CXCR1/CXCR2 receptors, on fever induced by either systemic administration of LPS or intracerebroventricular injection of CINC-1, as well as TNF-α, IL-1ß, IL-6, or ET-1, known mediators of febrile response. Our results show increased CINC-1 mRNA expression in the liver, hypothalamus, CSF, and plasma following LPS injection. Moreover, reparixin administered right before CINC-1 or LPS abolished the fever induced by CINC-1 and significantly reduced the response induced by LPS. In spite of these results, reparixin does not modify the fever induced by IL-1ß, TNF-α, and IL-6, but significantly reduces ET-1-induced fever. Therefore, it is plausible to suggest that CINC-1 might contribute to LPS-induced fever in rats by activating CXCR2 receptor on the CNS. Moreover, it can be hypothesized that CINC-1 is placed upstream TNF-α, IL-1ß, and IL-6 among the prostaglandin-dependent fever-mediator cascade and amidst the prostaglandin-independent synthesis pathway of fever.

Evaluation of antipyretic activity of Belladonna and Pyrogenium ultrahigh dilutions in induced fever model.

Background Belladonna and Pyrogenium are commonly used to treat fever in homeopathy. But in vivo antipyretic activity of these medicines is not reported yet. The study was conducted to evaluate the effectiveness of ultrahigh dilutions of Belladonna (Bell) and Pyrogenium (Pyro) in fever model of rabbits induced by Baker's yeast. Methods Healthy, local strain rabbits (♂ and ♀) were divided into seven groups (n=42): Normal control, negative control, standard control, pyro 1000c, pyro 200c, Bell 1000c and Bell 200c. Fever was induced by intra peritoneal injection of 135 mg/kg Baker's yeast suspension. Rectal temperature was measured hourly. All the medicines were administered once a day. The results were expressed as mean ± SEM. ANOVA and least significant difference post hoc test were applied for checking the level of significance, p-value of ≤0.05 was considered significant statistically. Results Pyro in both potencies significantly reduced fever in rabbits compared to negative control group, while both potencies of Bell were ineffective. Paracetamol and Pyro 1000c reduced by 1.2 °C (39.7 ± 0.1 to 38.5 ± 0.1), while Pyro 200c reduced by 1 °C temperature (39.7 ± 0.5 to 38.7 ± 0.2). Conclusions Pyro possesses marked antipyretic activity in rabbit's Baker's yeast fever model. It would embolden its clinical use in fever with more guarantee of its efficacy. However, caveat of small sample size necessitates replication of experiment in large sample size.